The long-term objective of the grantee is to develop a commercially viable alternative to hematopoietic stem cell (HSC) selection. This project proposes to validate a prototype for HSC selection based on a novel conductive polymeric technology. This project is divided into three specific aims. The first aim is a proof-of-concept study designed to evaluate specificity and capture efficiency using human cell lines. The second aim will purify HSC from human umbilical cord blood and bone marrow. The third aim will develop a novel monitoring system to detect changes in the membrane's electrical characteristics resulting from cell binding. The membrane system employs a specific antibody for HSC which is covalently attached to the conductive polymer matrix. Cell suspensions will be passed across the membrane, and direct cell capture and release will be rapidly achieved using low voltage. The use of a conductive polymeric surface enables monitoring of rapid and controlled cell binding and release. This technology promises significant improvements over existing cell selection methods in terms of sample processing time, reagents, and ease of use. Following validation and scale-up, this system will have immediate commercial uses in diagnostics, clinical transplantation, and basic research of HSC biology. PROPOSED COMMERCIAL APPLICATIONS: The potential commercial applications of the polymeric membrane selection system are in l) clinical autologous and allogeneic stem cell transplants, 2) cancer diagnostics, 3) ex-vivo expansion of stem cells, and 4) basic stem cell biology research.